After our original article on the possibilities of
using Melamine foam sound absorbing material for computer cases, we received a lot of good questions about testing other acoustic materials. Some requests were for tests of existing acoustic products, and other were
for simple everyday materials like corrugated cardboard. We will be doing our best to cover as many types of material as possible, so don't
be afraid to suggest something, or tell us what you use in
your case.

One of the alternatives we are looking at in this review is a product presented especially for use in the computer, namely Magic Fleece.

The two layers of material (shown here) are what allow the Magic Fleece to lower the sound output of a computer case by several dB's.

Noisecontrol's Magic Fleece is sold by the folks at Chillblast.com, a London based retailer. Noisecontrol are the same German company who make the Silverado - that heatsink with the pure silver base Toms Hardware made so famous.

Magic Fleece appears to be an acoustic layered
fiberglass felt which acts as a sound barrier, or dampener. The thick black sheets, of which there are five to a kit, measure 15.5" x 15.5" and are about 1/2" thick. The material is heavy, flexible, but is easy to cut and install in a case. The back of each sheet of Magic Fleece has been coated in an adhesive so it is really just a matter of cutting, peeling off the vinyl and sticking it into place. Instructions are included with the product, but they are written entirely in German, and my German is pretty poor.

After pulling the Melamine Foam out of the Antec test case, it took me about 15 minutes to install the Noisecontrol Magic Fleece in the same areas to get an equal and comparable basis. The size of each panel is pretty good for most cases, and we thankfully didn't have to make too many cuts to cover each of the side panels.

A sharp pair of scissors makes short work of the Magic Fleece and I highly recommend fitting all the panels before removing the backing and sticking them into place permanently. The last thing you want to do is try to reassemble the case only to find you have to make a few cuts here and there, but can't because the Magic Fleece is firmly attached.

The Test Environment

As we did before with the Melamine sound absorbing material we installed the Magic Fleece into an Antec SX1030B case and took some ambient sound measurement. Both side panels, the base, and the top of the case were covered in the Fleece. A small section was placed between the front bezel and the case blocking the front fan intakes, but no Magic Fleece was placed on the back of the computer case, where there are two fan exhausts.

These results, which were obtained with an Omega HHSL-1 sound level meter (range 35dba-130dBa), are shown in the chart below, along with the previous results with the Melamine foam. The sound meter was located approximately 8" away from the case for the front/side/rear noise measurements.

Case temperature was recorded with an Omega HH501DK digital thermometer by placing a Type-K thermocouple in the center of the case.

Measurement

No Sound Insulation

Melamine Foam

Magic Fleece

Ambient Sound Level:

47.4 dB

40.6 dB

40.5 dB

Front of Case:

54.2 dB

49.7 dB

46.9 dB

Side of Case:

53.3 dB

47.5 dB

46.3 dB

Rear of Case:

58.5 dB

56.1 dB

57.4 dB

Internal Case Temp.:

27.9 (C)

29.3 (C)

31.7 (C)

Ambient Temperature:

22.4 (C)

Keep in mind that a in most acoustic tests a drop of 3 dBa is hard to notice to the average human ear, but anything more should be easily perceptible.

The Noisecontrol Magic Fleece from Chillblast.com (cost:
£34) performed about the same as the Melamine Foam for the most part. Noise
levels from the side and front of the case were down by 2 or
3 dB over the melamine, but increased slightly out the back. The Magic Fleece did seem to raise the case temp just
slightly higher than the Melamine foam did, but other than that the results are quite good. While neither sound absorbing material made the computer dead silent, they both dropped the amount of noise escaping from the enclosure.

Results will vary, depending on the type of case you have, how carefully
and completely you line the inside of the case, and on how noisy individual components are, but for the most part the drop in noise is comes without much hassle and is more than welcome.

Magic Fleece, or any other sound absorbing material
works best when used with other sound conscious products - like the CNPS heatsinks from Zalman, and vibration isolators for hard drives for example. For those of you with 7000RPM Delta's who live by their powerful and noisy heatsinks, a little sound proofing can also be a good idea too.

As a readily available means of lowering the noise output
of a computer, Noisecontrol's Magic Fleece does the job as well as the other acoustic material we have tested (which had a NRC value of 0.90) and with a very simple installation procedure, it is worth considering.

Update: UpChillblast later sent us a copy of the english instructions for the Fleece.